Concurrent state machine processing using a blockchain
Trustless deterministic state machines can be implemented using a blockchain infrastructure and state machines can run concurrently over more than one blockchain transaction. The transactions can be done in a Bitcoin blockchain ledger. An unlocking transaction constraint that constrains an unlocking transaction to include a transaction input that references a previous transaction output is determined. A redeemable transaction is created to include a transaction output that includes an amount and a transaction locking script that includes the unlocking transaction constraint, with unlocking the amount being contingent upon execution of at least one unlocking script of the unlocking transaction satisfying the unlocking transaction constraint. The redeemable transaction is caused to be validated at a node of a blockchain network.
1. A computer-implemented method for effecting a state transition of a state machine in a blockchain network, the method comprising:
determining a current state of the state machine in a set of state rules from a previous blockchain transaction, wherein the current state is embedded in an output of the previous blockchain transaction;
creating an unlocking blockchain transaction comprising an input and the current state in an unlocking script of the unlocking blockchain transaction;
determining a next state of the state machine from the input, the current state, and the set of state rules, wherein the next state is embedded in a locking script of an output of the unlocking blockchain transaction; and
unlocking the output of the previous blockchain transaction to effect the state transition.
2. The computer-implemented method of claim 1 , further comprising encoding the set of state rules in a locking script of an output of the previous blockchain transaction.
3. The computer-implemented method of claim 1 , further comprising embedding the current state in a lock time field of a locking script of the previous blockchain transaction.
4. The computer-implemented method of claim 1 , further comprising determining that the input comprises external data determined at a time the unlocking blockchain transaction is created.
5. The computer-implemented method of claim 1 , further comprising the unlocking blockchain transaction accepting the input from a determined source.
6. The computer-implemented method of claim 1 , further comprising the set of state rules comprising a state-transaction matrix representing a constraint on the unlocking blockchain transaction imposed by a locking script.
7. The computer-implemented method of claim 6 , further comprising checking that the unlocking blockchain transaction includes an output that includes the next state in a particular field.
8. The computer-implemented method of claim 6 , further comprising encoding the set of state rules as a switch statement or another conditional statement.
9. The computer-implemented method of claim 1 , further comprising duplicating the locking script of the previous blockchain transaction output to every unlocking blockchain transaction that attempts to transfer control of a digital asset to a next transaction, which is linked to the previous transaction output.
10. The computer-implemented method of claim 9 , further comprising replicating this process until a termination condition is fulfilled.
11. The computer-implemented method of claim 1 , further comprising performing the method by a validation node in the blockchain network.
12. A system, comprising:
a processor; and
memory including executable instructions that, as a result of execution by the processor, cause the system to perform a computer-implemented method comprising:
determining a current state of a state machine in a set of state rules from a previous blockchain transaction, wherein the current state is embedded in an output of the previous blockchain transaction;
creating an unlocking blockchain transaction comprising an input and the current state in an unlocking script of the unlocking blockchain transaction;
determining a next state of the state machine from the input, the current state, and the set of state rules, wherein the next state is embedded in a locking script of an output of the unlocking blockchain transaction; and
unlocking the output of the previous blockchain transaction to effect the state transition.
13. The system of claim 12 , wherein the set of state rules is encoded in a locking script of an output of the previous blockchain transaction.
14. The system of claim 12 , wherein the current state is embedded in a lock time field of a locking script of the previous blockchain transaction.
15. The system of claim 12 , wherein the input comprises external data determined at a time the unlocking blockchain transaction is created.
16. The system of claim 12 , wherein the unlocking blockchain transaction is created to accept the input from a determined source.
17. The system of claim 12 , wherein the set of state rules comprises a state-transaction matrix represented by a constraint on the unlocking blockchain transaction imposed by a locking script.
18. The system of claim 17 , wherein the constraint comprises checking that the unlocking blockchain transaction includes an output that includes the next state in a particular field.
19. The system of claim 17 , wherein the set of state rules are encoded as a switch statement or another conditional statement.
20. A non-transitory computer-readable storage medium having stored thereon executable instructions that, as a result of being executed by a processor of a computer system, cause the computer system to at least perform the computer-implemented method according to claim 1 .